Liquid composition for preserving materials, particularly timber



Patented Dec. 6, 1932 UNITED STATES PATENT OFFICE FREDERICK ARTHUR HILL,OF EALING, LONDON, ENGLAND No Drawing.

This invention comprises improvements in or relating to liquidcompositions for preserving materials particularly timber.

Oreosote is used in large quantities for preserving railway sleepers andother timher, and one object of the present invention is to provide asubstitute for creosote which shall be less expensive but neverthelesssubstantially as effective as regards its preserva tive properties.

The composition provided according to this invention comprises a mixtureof crude oil, bituminous material, and a small tiroportion ofnaphthalene or other preservative adapted to prevent insect attack.

Preferably the basis of the composition is fuel oil (otherwise known asDiesel oil) that is to say, the petroleum product from which the lighterconstituents such as naphtha and the greater part of the illuminatingoils and kerosenes have been separated.

The term bituminous material is used to include natural and artificialasphalt, tar, pitch and the like and also mixtures of these substances.Preferably in carrying; out the invention bitumen of the typeartificially prepared from petroleum, such as Mexican asphalt, isemployed.

In one example according to the invention the composition was preparedin the following way. Mexican asphalt was first liquefied by heat andthere was then mixed with the molten asphalt a proportion of liquidnaphthalene prepared by melting crystals. The molten mixture of bitumenand naphthalene was then added to a main body of fuel oil and thoroughlyincorporated therewith by agitation in a mixer. The resultingcomposition contained 85% fuel oil, 10% asphalt and 5% naphthalene.

The proportions given above may be varied within comparatively widelimits without departing from the scope of the invention. One functionof the bitumen is to act as a pore-fillingmaterial, and the proportionof bitumen in the composition will naturally vary with the nature of thetimber to be treated. For example with a soft wood it may be desirableto have a comparatively high proportion of bitumen in the composi-Application filed May 15, 1930, Serial No. 452,816, and in Great BritainMarch 14, 1930.

accompany any increase in the proportion of bitumen with a correspondingincrease in the proportion of the naphthalene.

Some crude oils have as a natural constituent a substantial bitumencontent. When such oils are employed in the present invention, it mightnot be necessary to add a further proportion of bitumen, and in any casethe proportion of added bitumen would be less than the case where fueloil is used.

One advantage of this invention is that,

on account of the part played by the'bitumen, the cheaper and softerwoods, which have hitherto been found unsatisfactory for the manufactureof railway sleepers, may now be used for that purpose.

I claim:

A process for the manufacture of a liquid composition for preservingtimber which consists in preparing a molten mixture of asphalt andnaphthalene in the proportions of about 2 parts asphalt to 1 part ofnaphthalene, and thoroughly incorporating this mixture with a main bodyof fuel oil in proportions of about 15 parts asphalt-naphthalene mixtureto 85 parts fuel oil.

In testimony whereof I affix my signature.

FREDERICK ARTHUR HILL.

QTI

